Aiming at the complexity of kinetic analysis of spatial mechanism by analytical method, an analysis model is established in 3D Cartesian coordinate system. By mathematical modeling and algorithms, relationship formula of motion parameters is set up and the solutions of angular displacement, angular velocity and angular acceleration are obtained. Through computer-aided tools, the corresponding curves are plotted, even the correctness of analytical method is validated. In virtual prototype environment, the same analytical results are presented, giving above conclusions a convincing support. This dissertation actualizes the effective kinetic analysis of spatial RSSR mechanism and has valuable reference to the parametric analysis and design.